行為變更：所有應用程式

Android 16 平台包含可能對應用程式造成影響的行為變更。無論 targetSdkVersion 為何，當應用程式在 Android 16 上執行時，下列行為變更將會套用至所有應用程式。您應測試應用程式，並視需要修改，以便在適當情況下支援這些變更。

另請務必查看僅對指定 Android 16 為目標版本的應用程式造成影響的行為變更。

核心功能

Android 16 (API 級別 36) 包含下列變更，可修改或擴充 Android 系統的各種核心功能。

JobScheduler 配額最佳化

Starting in Android 16, we're adjusting regular and expedited job execution runtime quota based on the following factors:

Which app standby bucket the application is in: in Android 16, active standby buckets will start being enforced by a generous runtime quota.
If the job starts execution while the app is in a top state: in Android 16, Jobs started while the app is visible to the user and continues after the app becomes invisible, will adhere to the job runtime quota.
If the job is executing while running a Foreground Service: in Android 16, jobs that are executing concurrently with a foreground service will adhere to the job runtime quota. If you're leveraging jobs for user initiated data transfer, consider using user initiated data transfer jobs instead.

This change impacts tasks scheduled using WorkManager, JobScheduler, and DownloadManager. To debug why a job was stopped, we recommend logging why your job was stopped by calling WorkInfo.getStopReason() (for JobScheduler jobs, call JobParameters.getStopReason()).

For information about how your app's state affects the resources it can use, see Power management resource limits. For more information on battery-optimal best practices, refer to guidance on optimize battery use for task scheduling APIs.

We also recommend leveraging the new JobScheduler#getPendingJobReasonsHistory API introduced in Android 16 to understand why a job has not executed.

Testing

To test your app's behavior, you can enable override of certain job quota optimizations as long as the app is running on an Android 16 device.

To disable enforcement of "top state will adhere to job runtime quota", run the following adb command:

adb shell am compat enable OVERRIDE_QUOTA_ENFORCEMENT_TO_TOP_STARTED_JOBS APP_PACKAGE_NAME

To disable enforcement of "jobs that are executing while concurrently with a foreground service will adhere to the job runtime quota", run the following adb command:

adb shell am compat enable OVERRIDE_QUOTA_ENFORCEMENT_TO_FGS_JOBS APP_PACKAGE_NAME

To test certain app standby bucket behavior, you can set the app standby bucket of your app using the following adb command:

adb shell am set-standby-bucket APP_PACKAGE_NAME active|working_set|frequent|rare|restricted

To understand the app standby bucket your app is in, you can get the app standby bucket of your app using the following adb command:

adb shell am get-standby-bucket APP_PACKAGE_NAME

放棄空白工作停止原因

An abandoned job occurs when the JobParameters object associated with the job has been garbage collected, but JobService#jobFinished(JobParameters, boolean) has not been called to signal job completion. This indicates that the job may be running and being rescheduled without the app's awareness.

Apps that rely on JobScheduler, don't maintain a strong reference to the JobParameters object, and timeout will now be granted the new job stop reason STOP_REASON_TIMEOUT_ABANDONED, instead of STOP_REASON_TIMEOUT.

If there are frequent occurrences of the new abandoned stop reason, the system will take mitigation steps to reduce job frequency.

Apps should use the new stop reason to detect and reduce abandoned jobs.

If you're using WorkManager, AsyncTask, or DownloadManager, you aren't impacted because these APIs manage the job lifecycle on your app's behalf.

完全淘汰 JobInfo#setImportantWhileForeground

The JobInfo.Builder#setImportantWhileForeground(boolean) method indicates the importance of a job while the scheduling app is in the foreground or when temporarily exempted from background restrictions.

This method has been deprecated since Android 12 (API level 31). Starting in Android 16, it no longer functions effectively and calling this method will be ignored.

This removal of functionality also applies to JobInfo#isImportantWhileForeground(). Starting in Android 16, if the method is called, the method returns false.

已排序的廣播優先順序範圍不再是全域

Android apps are allowed to define priorities on broadcast receivers to control the order in which the receivers receive and process the broadcast. For manifest-declared receivers, apps can use the android:priority attribute to define the priority and for context-registered receivers, apps can use the IntentFilter#setPriority() API to define the priority. When a broadcast is sent, the system delivers it to receivers in order of their priority, from highest to lowest.

In Android 16, broadcast delivery order using the android:priority attribute or IntentFilter#setPriority() across different processes will not be guaranteed. Broadcast priorities will only be respected within the same application process rather than across all processes.

Also, broadcast priorities will be automatically confined to the range (SYSTEM_LOW_PRIORITY + 1, SYSTEM_HIGH_PRIORITY - 1). Only system components will be allowed to set SYSTEM_LOW_PRIORITY, SYSTEM_HIGH_PRIORITY as broadcast priority.

Your app might be impacted if it does either of the following:

Your application has declared multiple processes with the same broadcast intent, and has expectations around receiving those intents in a certain order based on the priority.
Your application process interacts with other processes and has expectations around receiving a broadcast intent in a certain order.

If the processes need to coordinate with each other, they should communicate using other coordination channels.

ART 內部變更

Android 16 includes the latest updates to the Android Runtime (ART) that improve the Android Runtime's (ART's) performance and provide support for additional Java features. Through Google Play System updates, these improvements are also available to over a billion devices running Android 12 (API level 31) and higher.

As these changes are released, libraries and app code that rely on internal structures of ART might not work correctly on devices running Android 16, along with earlier Android versions that update the ART module through Google Play system updates.

Relying on internal structures (such as non-SDK interfaces) can always lead to compatibility problems, but it's particularly important to avoid relying on code (or libraries containing code) that leverages internal ART structures, since ART changes aren't tied to the platform version the device is running on and they go out to over a billion devices through Google Play system updates.

All developers should check whether their app is impacted by testing their apps thoroughly on Android 16. In addition, check the known issues to see if your app depends on any libraries that we've identified that rely on internal ART structures. If you do have app code or library dependencies that are affected, seek public API alternatives whenever possible and request public APIs for new use cases by creating a feature request in our issue tracker.

16 KB 頁面大小相容模式

Android 15 推出了 16 KB 記憶體分頁支援功能，以提升平台效能。Android 16 新增了相容模式，可讓為 4 KB 記憶體分頁建構的部分應用程式，在針對 16 KB 記憶體分頁設定的裝置上執行。

當應用程式在搭載 Android 16 以上版本的裝置上執行時，如果 Android 偵測到應用程式有 4 KB 對齊的記憶體分頁，就會自動使用相容性模式，並向使用者顯示通知對話方塊。在 AndroidManifest.xml 中設定 android:pageSizeCompat 屬性以啟用向後相容性模式，可防止應用程式啟動時顯示對話方塊。如要使用 android:pageSizeCompat 屬性，請使用 Android 16 SDK 編譯應用程式。

為獲得最佳效能、可靠性和穩定性，應用程式仍應以 16 KB 對齊。如要進一步瞭解如何更新應用程式以支援 16 KB 記憶體分頁，請參閱近期的網誌文章。

系統偵測到 4 KB 對齊的應用程式在 16 KB 對齊的情況下執行時，可獲得更佳的效能時，會顯示相容模式對話方塊。

使用者體驗和系統 UI

Android 16 (API 級別 36) 包含下列變更，旨在打造更一致、直覺的使用者體驗。

Android 16 deprecates accessibility announcements, characterized by the use of announceForAccessibility or the dispatch of TYPE_ANNOUNCEMENT accessibility events. These can create inconsistent user experiences for users of TalkBack and Android's screen reader, and alternatives better serve a broader range of user needs across a variety of Android's assistive technologies.

Examples of alternatives:

For significant UI changes like window changes, use Activity.setTitle(CharSequence) and setAccessibilityPaneTitle(java.lang.CharSequence). In Compose, use Modifier.semantics { paneTitle = "paneTitle" }
To inform the user of changes to critical UI, use setAccessibilityLiveRegion(int). In Compose, use Modifier.semantics { liveRegion = LiveRegionMode.[Polite|Assertive]} . These should be used sparingly as they may generate announcements every time a View is updated.
To notify users about errors, send an AccessibilityEvent of type AccessibilityEvent#CONTENT_CHANGE_TYPE_ERROR and set AccessibilityNodeInfo#setError(CharSequence), or use TextView#setError(CharSequence).

The reference documentation for the deprecated announceForAccessibility API includes more details about suggested alternatives.

支援三按鈕操作模式

Android 16 為已正確遷移至預測返回功能的應用程式，提供 3 鍵導覽的預測返回功能支援。長按返回按鈕會啟動預測返回動畫，讓您預覽返回滑動手勢會帶您前往的位置。

這項行為適用於系統中所有支援預測返回動畫的區域，包括系統動畫 (返回首頁、跨工作和跨活動)。

在 3 個按鈕操作模式中，預測返回動畫。

自動套用主題色應用程式圖示

Beginning with Android 16 QPR 2, Android automatically applies themes to app icons to create a cohesive home screen experience. This occurs if an app does not provide its own themed app icon. Apps can control the design of their themed app icon by including a monochrome layer within their adaptive icon and previewing what their app icon will look like in Android Studio.

裝置板型規格

Android 16 (API 級別 36) 包含以下變更，適用於虛擬裝置擁有者將應用程式投放到螢幕時。

虛擬裝置擁有者覆寫

A virtual device owner is a trusted or privileged app that creates and manages a virtual device. Virtual device owners run apps on a virtual device and then project the apps to the display of a remote device, such as a personal computer, virtual reality device, or car infotainment system. The virtual device owner is on a local device, such as a mobile phone.

Virtual device owner on phone creates virtual device that projects app to remote display.

Per-app overrides

On devices running Android 16 (API level 36), virtual device owners can override app settings on select virtual devices that the virtual device owners manage. For example, to improve app layout, a virtual device owner can ignore orientation, aspect ratio, and resizability restrictions when projecting apps onto an external display.

Common breaking changes

The Android 16 behavior might impact your app's UI on large screen form factors such as car displays or Chromebooks, especially layouts that were designed for small displays in portrait orientation. To learn how to make your app adaptive for all device form factors, see About adaptive layouts.

References

Companion app streaming

安全性

Android 16 (API 級別 36) 包含多項異動，可提升系統安全性，協助保護應用程式和使用者免受惡意應用程式侵害。

安全性提高，避免意圖重新導向攻擊

Android 16 provides default security against general Intent redirection attacks, with minimum compatibility and developer changes required.

We are introducing by-default security hardening solutions to Intent redirection exploits. In most cases, apps that use intents normally won't experience any compatibility issues; we've gathered metrics throughout our development process to monitor which apps might experience breakages.

Intent redirection in Android occurs when an attacker can partly or fully control the contents of an intent used to launch a new component in the context of a vulnerable app, while the victim app launches an untrusted sub-level intent in an extras field of an ("top-level") Intent. This can lead to the attacker app launching private components in the context of the victim app, triggering privileged actions, or gaining URI access to sensitive data, potentially leading to data theft and arbitrary code execution.

Opt out of Intent redirection handling

Android 16 introduces a new API that allows apps to opt out of launch security protections. This might be necessary in specific cases where the default security behavior interferes with legitimate app use cases.

For applications compiling against Android 16 (API level 36) SDK or higher

You can directly use the removeLaunchSecurityProtection() method on the Intent object.

val i = intent
val iSublevel: Intent? = i.getParcelableExtra("sub_intent")
iSublevel?.removeLaunchSecurityProtection() // Opt out from hardening
iSublevel?.let { startActivity(it) }

For applications compiling against Android 15 (API level 35) or lower

While not recommended, you can use reflection to access the removeLaunchSecurityProtection() method.

val i = intent
val iSublevel: Intent? = i.getParcelableExtra("sub_intent", Intent::class.java)
try {
    val removeLaunchSecurityProtection = Intent::class.java.getDeclaredMethod("removeLaunchSecurityProtection")
    removeLaunchSecurityProtection.invoke(iSublevel)
} catch (e: Exception) {
    // Handle the exception, e.g., log it
} // Opt-out from the security hardening using reflection
iSublevel?.let { startActivity(it) }

隨附應用程式不會再收到探索逾時通知

Android 16 在配件裝置配對流程中導入了新行為，以保護使用者的所在位置隱私，避免遭到惡意應用程式竊取。所有在 Android 16 上執行的隨附應用程式，都不再直接透過 RESULT_DISCOVERY_TIMEOUT 收到發現逾時的通知。而是透過視覺對話方塊通知使用者逾時事件。當使用者關閉對話方塊時，應用程式會收到關於 RESULT_USER_REJECTED 關聯失敗的警示。

搜尋時間也從原本的 20 秒延長，使用者可在搜尋期間的任何時間停止裝置探索。如果在開始搜尋的頭 20 秒內發現至少一台裝置，CDM 就會停止搜尋其他裝置。

連線能力

Android 16 (API 級別 36) 包含藍牙堆疊的下列變更，可提升與周邊裝置的連線能力。

改善債券損失處理方式

自 Android 16 起，我們已更新藍牙堆疊，以便在偵測到遠端連結遺失時，提升安全性和使用者體驗。先前系統會自動移除配對連結，並啟動新的配對程序，這可能會導致不小心重新配對。我們發現許多應用程式並未以一致的方式處理連結失效事件。

為統一使用體驗，Android 16 改善了系統的連結遺失處理方式。如果先前已配對的藍牙裝置無法在重新連線時驗證，系統會中斷連結、保留本機配對資訊，並顯示系統對話方塊，告知使用者配對失敗，並引導他們重新配對。